Infrastructure as code offers a lower maintenance cost over time in many scenarios.

Sure you can click to set up WordPress on other hosts.

But how do you scale capacity of the servers or the database? How do you peer the network to your other cloud resources? How do you mirror the stack in another region?

With CloudFormation resource management is a few API calls away.

You can also use CloudFormation in point and click mode to create a stack and update its resources.

It may be overkill for some cases but for serious systems it's the best practice.